Roe are the eggs of female fish, enclosed in an ovarian membrane. Roe of some fish species is considered a great delicacy, the most famous being sturgeon roe . The processed salted roe of sturgeons is called caviar.
Top-quality processed roe must be absolutely fresh, and the individual eggs unbroken. When bitten, they must burst easily and feel soft, not at all rubbery or hard. The roe must have a pleasant, not fishy, taste and scent, and there should not be extra liquid visible among the eggs.